drivers/power/pda_power.c

   1 /*
   2  * Common power driver for PDAs and phones with one or two external
   3  * power supplies (AC/USB) connected to main and backup batteries,
   4  * and optional builtin charger.
   5  *
   6  * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/power_supply.h>
  17 #include <linux/pda_power.h>
  18 #include <linux/timer.h>
  19 #include <linux/jiffies.h>
  20
  21 static inline unsigned int get_irq_flags(struct resource *res)
  22 {
  23         unsigned int flags = IRQF_DISABLED | IRQF_SHARED;
  24
  25         flags |= res->flags & IRQF_TRIGGER_MASK;
  26
  27         return flags;
  28 }
  29
  30 static struct device *dev;
  31 static struct pda_power_pdata *pdata;
  32 static struct resource *ac_irq, *usb_irq;
  33 static struct timer_list charger_timer;
  34 static struct timer_list supply_timer;
  35
  36 static int pda_power_get_property(struct power_supply *psy,
  37                                   enum power_supply_property psp,
  38                                   union power_supply_propval *val)
  39 {
  40         switch (psp) {
  41         case POWER_SUPPLY_PROP_ONLINE:
  42                 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
  43                         val->intval = pdata->is_ac_online ?
  44                                       pdata->is_ac_online() : 0;
  45                 else
  46                         val->intval = pdata->is_usb_online ?
  47                                       pdata->is_usb_online() : 0;
  48                 break;
  49         default:
  50                 return -EINVAL;
  51         }
  52         return 0;
  53 }
  54
  55 static enum power_supply_property pda_power_props[] = {
  56         POWER_SUPPLY_PROP_ONLINE,
  57 };
  58
  59 static char *pda_power_supplied_to[] = {
  60         "main-battery",
  61         "backup-battery",
  62 };
  63
  64 static struct power_supply pda_power_supplies[] = {
  65         {
  66                 .name = "ac",
  67                 .type = POWER_SUPPLY_TYPE_MAINS,
  68                 .supplied_to = pda_power_supplied_to,
  69                 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  70                 .properties = pda_power_props,
  71                 .num_properties = ARRAY_SIZE(pda_power_props),
  72                 .get_property = pda_power_get_property,
  73         },
  74         {
  75                 .name = "usb",
  76                 .type = POWER_SUPPLY_TYPE_USB,
  77                 .supplied_to = pda_power_supplied_to,
  78                 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
  79                 .properties = pda_power_props,
  80                 .num_properties = ARRAY_SIZE(pda_power_props),
  81                 .get_property = pda_power_get_property,
  82         },
  83 };
  84
  85 static void update_charger(void)
  86 {
  87         if (!pdata->set_charge)
  88                 return;
  89
  90         if (pdata->is_ac_online && pdata->is_ac_online()) {
  91                 dev_dbg(dev, "charger on (AC)\n");
  92                 pdata->set_charge(PDA_POWER_CHARGE_AC);
  93         } else if (pdata->is_usb_online && pdata->is_usb_online()) {
  94                 dev_dbg(dev, "charger on (USB)\n");
  95                 pdata->set_charge(PDA_POWER_CHARGE_USB);
  96         } else {
  97                 dev_dbg(dev, "charger off\n");
  98                 pdata->set_charge(0);
  99         }
 100
 101         return;
 102 }
 103
 104 static void supply_timer_func(unsigned long irq)
 105 {
 106         if (ac_irq && irq == ac_irq->start)
 107                 power_supply_changed(&pda_power_supplies[0]);
 108         else if (usb_irq && irq == usb_irq->start)
 109                 power_supply_changed(&pda_power_supplies[1]);
 110         return;
 111 }
 112
 113 static void charger_timer_func(unsigned long irq)
 114 {
 115         update_charger();
 116
 117         /* Okay, charger set. Now wait a bit before notifying supplicants,
 118          * charge power should stabilize. */
 119         supply_timer.data = irq;
 120         mod_timer(&supply_timer,
 121                   jiffies + msecs_to_jiffies(pdata->wait_for_charger));
 122         return;
 123 }
 124
 125 static irqreturn_t power_changed_isr(int irq, void *unused)
 126 {
 127         /* Wait a bit before reading ac/usb line status and setting charger,
 128          * because ac/usb status readings may lag from irq. */
 129         charger_timer.data = irq;
 130         mod_timer(&charger_timer,
 131                   jiffies + msecs_to_jiffies(pdata->wait_for_status));
 132         return IRQ_HANDLED;
 133 }
 134
 135 static int pda_power_probe(struct platform_device *pdev)
 136 {
 137         int ret = 0;
 138
 139         dev = &pdev->dev;
 140
 141         if (pdev->id != -1) {
 142                 dev_err(dev, "it's meaningless to register several "
 143                         "pda_powers; use id = -1\n");
 144                 ret = -EINVAL;
 145                 goto wrongid;
 146         }
 147
 148         pdata = pdev->dev.platform_data;
 149
 150         update_charger();
 151
 152         if (!pdata->wait_for_status)
 153                 pdata->wait_for_status = 500;
 154
 155         if (!pdata->wait_for_charger)
 156                 pdata->wait_for_charger = 500;
 157
 158         setup_timer(&charger_timer, charger_timer_func, 0);
 159         setup_timer(&supply_timer, supply_timer_func, 0);
 160
 161         ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
 162         usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
 163         if (!ac_irq && !usb_irq) {
 164                 dev_err(dev, "no ac/usb irq specified\n");
 165                 ret = -ENODEV;
 166                 goto noirqs;
 167         }
 168
 169         if (pdata->supplied_to) {
 170                 pda_power_supplies[0].supplied_to = pdata->supplied_to;
 171                 pda_power_supplies[1].supplied_to = pdata->supplied_to;
 172                 pda_power_supplies[0].num_supplicants = pdata->num_supplicants;
 173                 pda_power_supplies[1].num_supplicants = pdata->num_supplicants;
 174         }
 175
 176         ret = power_supply_register(&pdev->dev, &pda_power_supplies[0]);
 177         if (ret) {
 178                 dev_err(dev, "failed to register %s power supply\n",
 179                         pda_power_supplies[0].name);
 180                 goto supply0_failed;
 181         }
 182
 183         ret = power_supply_register(&pdev->dev, &pda_power_supplies[1]);
 184         if (ret) {
 185                 dev_err(dev, "failed to register %s power supply\n",
 186                         pda_power_supplies[1].name);
 187                 goto supply1_failed;
 188         }
 189
 190         if (ac_irq) {
 191                 ret = request_irq(ac_irq->start, power_changed_isr,
 192                                   get_irq_flags(ac_irq), ac_irq->name,
 193                                   &pda_power_supplies[0]);
 194                 if (ret) {
 195                         dev_err(dev, "request ac irq failed\n");
 196                         goto ac_irq_failed;
 197                 }
 198         }
 199
 200         if (usb_irq) {
 201                 ret = request_irq(usb_irq->start, power_changed_isr,
 202                                   get_irq_flags(usb_irq), usb_irq->name,
 203                                   &pda_power_supplies[1]);
 204                 if (ret) {
 205                         dev_err(dev, "request usb irq failed\n");
 206                         goto usb_irq_failed;
 207                 }
 208         }
 209
 210         goto success;
 211
 212 usb_irq_failed:
 213         if (ac_irq)
 214                 free_irq(ac_irq->start, &pda_power_supplies[0]);
 215 ac_irq_failed:
 216         power_supply_unregister(&pda_power_supplies[1]);
 217 supply1_failed:
 218         power_supply_unregister(&pda_power_supplies[0]);
 219 supply0_failed:
 220 noirqs:
 221 wrongid:
 222 success:
 223         return ret;
 224 }
 225
 226 static int pda_power_remove(struct platform_device *pdev)
 227 {
 228         if (usb_irq)
 229                 free_irq(usb_irq->start, &pda_power_supplies[1]);
 230         if (ac_irq)
 231                 free_irq(ac_irq->start, &pda_power_supplies[0]);
 232         del_timer_sync(&charger_timer);
 233         del_timer_sync(&supply_timer);
 234         power_supply_unregister(&pda_power_supplies[1]);
 235         power_supply_unregister(&pda_power_supplies[0]);
 236         return 0;
 237 }
 238
 239 static struct platform_driver pda_power_pdrv = {
 240         .driver = {
 241                 .name = "pda-power",
 242         },
 243         .probe = pda_power_probe,
 244         .remove = pda_power_remove,
 245 };
 246
 247 static int __init pda_power_init(void)
 248 {
 249         return platform_driver_register(&pda_power_pdrv);
 250 }
 251
 252 static void __exit pda_power_exit(void)
 253 {
 254         platform_driver_unregister(&pda_power_pdrv);
 255         return;
 256 }
 257
 258 module_init(pda_power_init);
 259 module_exit(pda_power_exit);
 260 MODULE_LICENSE("GPL");
 261 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");